| genetic evidence that the vibrio cholerae monolayer is a distinct stage in biofilm development. | biofilm development is conceived as a developmental process in which free swimming cells attach to a surface, first transiently and then permanently, as a single layer. this monolayer of immobilized cells gives rise to larger cell clusters that eventually develop into the biofilm, a three-dimensional structure consisting of large pillars of bacteria interspersed with water channels. previous studies have shown that efficient development of the vibrio cholerae biofilm requires a combination of pi ... | 2004 | 15066042 |
| phenotypic and genotypic characteristics and epidemiological significance of ctx+ strains of vibrio cholerae isolated from seafood in malaysia. | of 97 strains of vibrio cholerae isolated from various seafoods in malaysia in 1998 and 1999, 20 strains carried the ctx gene and produced cholera toxin. fourteen, one, and five of these toxigenic strains belonged to the o139, o1 ogawa, and rough serotypes, respectively. the rough strains had the rfb gene of the o1 serotype. the toxigenic strains varied in their biochemical characteristics, the amount of cholera toxin produced, their antibiograms, and the presence or absence of the ptlc plasmid ... | 2004 | 15066786 |
| a cellular metalloproteinase activates vibrio cholerae pro-cytolysin. | many strains of vibrio cholerae produce a cytolysin (vcc) that forms oligomeric transmembrane pores in animal cells. the molecule is secreted as a procytolysin (pro-vcc) of 79 kda that must be cleaved at the n terminus to generate the active 65-kda toxin. processing can occur in solution, and previous studies have described the action of mature vcc thus generated. however, little is known about the properties of pro-vcc itself. in this study, it is shown that pro-vcc exist as a monomer in soluti ... | 2004 | 15066987 |
| the effect of delta g on the transport and oral absorption of macromolecules. | delta g (deltag) is the biologically active fragment of zonula occludens toxin (zot), an absorption enhancer, that reversibly opens the tight junctions of epithelial and endothelial cells in the small intestine and brain. this study evaluates the possible use of deltag in enhancing the oral bioavailability of macromolecules using large paracellular markers as model agents. the transport of [(14)c]inulin and [(14)c]peg4000 was evaluated across caco-2 cells with deltag (0, 100, 180 microg/ml). the ... | 2004 | 15067707 |
| australia's notifiable diseases status, 2002: annual report of the national notifiable diseases surveillance system. | there were 57 infectious diseases notifiable at the national level in australia in 2002. states and territories reported 100,278 cases of infectious diseases to the national notifiable diseases surveillance system (nndss), a fall of 4 per cent compared to the number of notifications in 2001. in 2002, the most frequently notified diseases were, sexually transmitted infections (31,929 reports, 32% of total notifications), gastrointestinal infections (26,708 reports, 27% of total notifications) and ... | 2004 | 15072156 |
| the crystal structure of the periplasmic domain of the type ii secretion system protein epsm from vibrio cholerae: the simplest version of the ferredoxin fold. | the terminal branch of the general secretion pathway (gsp or type ii secretion system) is used by several pathogenic bacteria for the secretion of their virulence factors across the outer membrane. in these secretion systems, a complex of 12-15 gsp proteins spans from the pore in the outer membrane via several associated signal or energy-transducing proteins in the inner membrane to a regulating atpase in the cytosol. the human pathogen vibrio cholerae uses such a system, called the eps system, ... | 2004 | 15081815 |
| [factors influencing the capacity of cellular substrate adherence of vibrio cholerae o1 and non o1 strains]. | bacterial adherence to eukariotic cells represents an important step of tissue colonization and is mediated by specific molecules called adhesins. bacterial adherence to cellular substrate is a very complex process consisting in specific interactions between the surface of host cell and bacterial cell surface respectively. adherence to cellular substrate confers selective advantages to bacterial cells, as: rapid growth rate by shorter lag period and protection against antibodies and lysozime. ad ... | 2002 | 15085599 |
| [study of antibiotic influence on adherence capacity of gram positive and gram negative bacteria to the cellular substrate]. | bacterial adherence to the cellular substrate (skin and mucosa) represents a precondition of infectious pathology. it was demonstrated that bacteria which adhere and form biofilms on catheters and other inert materials used in medicine are resistant to the therapeutic antibiotic concentrations being protected by the biofilm mathrix and generating severe and hard to treat infections. there are only few studies on the influence of antibiotics on the bacterial adhesins synthesis and bacterial adher ... | 2002 | 15085601 |
| formation of sxt tandem arrays and sxt-r391 hybrids. | sxt is an integrative and conjugative element (ice) isolated from vibrio cholerae. this approximately 100-kb ice encodes resistance to multiple antibiotics and integrates site specifically into the chromosome. sxt excises from the chromosome to form a circular but nonreplicative extrachromosomal molecule that is required for its transfer. here we found that a significant fraction of freshly isolated sxt exconjugants contained tandem sxt arrays. there was heterogeneity in the size of the sxt arra ... | 2004 | 15090504 |
| highly divergent rfah orthologs from pathogenic proteobacteria can substitute for escherichia coli rfah both in vivo and in vitro. | the transcriptional enhancer protein rfah positively regulates production of virulence factors in escherichia coli and salmonella enterica serovar typhimurium via a cis element, ops. genes coding for rfah orthologs were identified in conceptually translated genomes of bacterial pathogens, including vibrio and yersinia spp. we cloned the rfah genes from vibrio cholerae, yersinia enterocolitica, s. enterica serovar typhimurium, and klebsiella pneumoniae into e. coli expression vectors. purified rf ... | 2004 | 15090525 |
| type iv pilus structure and bacterial pathogenicity. | | 2004 | 15100690 |
| cefotaximases (ctx-m-ases), an expanding family of extended-spectrum beta-lactamases. | among the extended-spectrum beta-lactamases, the cefotaximases (ctx-m-ases) constitute a rapidly growing cluster of enzymes that have disseminated geographically. the ctx-m-ases, which hydrolyze cefotaxime efficiently, are mostly encoded by transferable plasmids, and the enzymes have been found predominantly in enterobacteriaceae, most prevalently in escherichia coli, salmonella typhimurium, klebsiella pneumoniae, and proteus mirabilis. isolates of vibrio cholerae, acinetobacter baumannii, and a ... | 2004 | 15105882 |
| virulence properties of rough and smooth strains of vibrio cholerae o1. | a comparative study was carried out to see the differences in pathogenicity of rough and smooth strains. a total of 10 strains including 5 each of rough and smooth strains of vibrio cholerae o1 were tested and found positive for toxin production by enzyme-linked immunosorbent assay (elisa) in richardson's and aki media. all the smooth and rough strains, except one, showed a titre of 1: 10 and 1: 100 in richardson's and aki media, respectively. both types of strains produced enterotoxin in rabbit ... | 2004 | 15107532 |
| toxin-coregulated pilus-loaded microparticles as a vaccine against vibrio cholerae o139. | | 2004 | 15109462 |
| phylogeny of gamma-proteobacteria: resolution of one branch of the universal tree? | the reconstruction of bacterial evolutionary relationships has proven to be a daunting task because variable mutation rates and horizontal gene transfer (hgt) among species can cause grave incongruities between phylogenetic trees based on single genes. recently, a highly robust phylogenetic tree was constructed for 13 gamma-proteobacteria using the combined alignments of 205 conserved orthologous proteins.1 only two proteins had incongruent tree topologies, which were attributed to hgt between p ... | 2004 | 15112225 |
| microbial-gut interactions in health and disease. epithelial cell responses. | pathogenic bacteria use many strategies to secure their survival within the host. enteropathogens exploit intestinal epithelial cells in many ways, including the manipulation of normal cellular functioning, or of cellular structural components, or by the induction of signalling pathways, such as the production of pro-inflammatory cytokines. however, the enterocyte warns the host of impending danger and, in turn, elicits a protective response. pathogens are detected by epithelial cells owing to t ... | 2004 | 15123076 |
| branching sites and morphological abnormalities behave as ectopic poles in shape-defective escherichia coli. | certain mutants in escherichia coli lacking multiple penicillin-binding proteins (pbps) produce misshapen cells containing kinks, bends and branches. these deformed regions exhibit two structural characteristics of normal cell poles: the peptidoglycan is inert to dilution by new synthesis or turnover, and a similarly stable patch of outer membrane caps the sites. to test the premise that these aberrant sites represent biochemically functional but misplaced cell poles, we assessed the intracellul ... | 2004 | 15130123 |
| microbial contamination of drinking water and disease outcomes in developing regions. | drinking water is a major source of microbial pathogens in developing regions, although poor sanitation and food sources are integral to enteric pathogen exposure. gastrointestinal disease outcomes are also more severe, due to under-nutrition and lack of intervention strategies in these regions. poor water quality, sanitation and hygiene account for some 1.7 million deaths a year world-wide (3.1% of all deaths and 3.7% of all daly's), mainly through infectious diarrhoea. nine out of 10 such deat ... | 2004 | 15138046 |
| detection of vibrio parahaemolyticus and vibrio cholerae in oyster, crassostrea rhizophorae, collected from a natural nursery in the cocó river estuary, fortaleza, ceará, brazil. | oysters are edible organisms that are often ingested partially cooked or even raw, presenting therefore a very high risk to the consumers' health, especially in tropical regions. the presence of vibrio cholerae and vibrio parahaemolyticus in oysters sampled at an estuary in the brazilian northeastern region was studied, with 300 oysters tested through an 8-months period. the salinity of the water at the sampling point varied between 3% and 27. v. cholerae was the most frequently detected species ... | 2004 | 15141271 |
| use of reca as an alternative phylogenetic marker in the family vibrionaceae. | this study analysed the usefulness of reca gene sequences as an alternative phylogenetic and/or identification marker for vibrios. the reca sequences suggest that the genus vibrio is polyphyletic. the high heterogeneity observed within vibrios was congruent with former polyphasic taxonomic studies on this group. photobacterium species clustered together and apparently nested within vibrios, while grimontia hollisae was apart from other vibrios. within the vibrios, vibrio cholerae and vibrio mimi ... | 2004 | 15143042 |
| [cloning and expression of immunoadjuvant molecule--ctb gene]. | we cloned cholera toxin subunit b gene from 569b and m045 strain of vibrio cholerae with polymerase chain reaction, constructed recombinant plasmid pctb, and transformed pctb into the prokaryotic cell strain jm109. the indentification was made by means of restriction enzyme analysis, polymerase chain reaction, dna sequencing, sds-polyacrylamine gel electrophoresis analysis and western blot. the results indicate that we have amplified cholera toxin subunit b gene of 376 bp from vibrio cholerae an ... | 2004 | 15143552 |
| identification of cryptochrome dash from vertebrates. | a new type of cryptochrome, cry-dash, has been recently identified. the cry-dash proteins constitute the fifth subfamily of the photolyase/cryptochrome family. cry-dashs have been identified from synechocystis sp. pcc 6803, vibrio cholerae, and arabidopsis thaliana. the synechocystis cry-dash was the first cryptochrome identified from bacteria, and its biochemical features and tertiary structure have been extensively investigated. to determine how broadly the subfamily is distributed within livi ... | 2004 | 15147276 |
| experimental immunisation and protection of guinea pigs with vibrio cholerae toxoid and mucinases, neuraminidase and proteinase. | as measured by fluid accumulation in ileal loops, vibrio cholerae mucinase complex, with or without toxoid, protected guinea pigs from challenges with v. cholerae live organisms and enterotoxin. the neuraminidase and proteinases of the complex were combined in modified oil emulsion or aluminum hydroxide adjuvants and the resultant vaccines given by the parenteral or oral routes. there was little difference between the two types of adjuvant. control of stomach acidity improved oral vaccination. a ... | 2004 | 15149770 |
| characterization of the icmh and icmf genes required for legionella pneumophila intracellular growth, genes that are present in many bacteria associated with eukaryotic cells. | legionella pneumophila, the causative agent of legionnaires' disease, replicates intracellularly within a specialized phagosome of mammalian and protozoan host cells, and the icm/dot type iv secretion system has been shown to be essential for this process. unlike all the other known icm/dot proteins, the icmf protein, which was described before, and the icmh protein, which is characterized here, have homologous proteins in many bacteria (such as yersinia pestis, salmonella enterica, rhizobium le ... | 2004 | 15155646 |
| the vibrio cholerae toxr-regulated porin ompu confers resistance to antimicrobial peptides. | bpi (bactericidal/permeability-increasing) is a potent antimicrobial protein that was recently reported to be expressed as a surface protein on human gastrointestinal tract epithelial cells. in this study, we investigated the resistance of vibrio cholerae, a small-bowel pathogen that causes cholera, to a bpi-derived peptide, p2. unlike in escherichia coli and salmonella enterica serovar typhimurium, resistance to p2 in v. cholerae was not dependent on the bipa gtpase. instead, we found that toxr ... | 2004 | 15155667 |
| abundance in sewage of bacteriophages infecting escherichia coli o157:h7. | bacterial virulence factors such as toxins are often encoded by bacteriophages. among other examples, factors encoded by phages have been described in some of the emerging or re-emerging pathogens, including the pyrogenic exotoxin a production in group a streptococci, the cholera toxin in vibrio cholerae, or enterotoxin production in enterohemorrhagic (ehec) strains of e. coli. most described virulence factors in shiga toxin (stx)-producing e. coli strains are located in mobile genetic elements ... | 2004 | 15156020 |
| transcriptional analysis and operon structure of the taga-orf2-orf3-mop-tagd region on the vibrio pathogenicity island in epidemic v. cholerae. | the vibrio pathogenicity island (vpi) in epidemic vibrio cholerae is an essential virulence gene cluster. the vpi can excise from the chromosome and form extrachromosomal circular excision products. the vpi is 41.2-kb in size and encodes 29 potential proteins, several of which have no known function and whose regulation is not well understood. to determine the transcriptional organization of the taga-orf2-orf3-mop-tagd region located at the 5'-(left) end of the vpi, we used reverse-transcriptase ... | 2004 | 15158282 |
| association of adherence and motility in interleukin 8 induction in human intestinal epithelial cells by vibrio cholerae. | interleukin 8 (il-8) mrna expression in vibrio cholerae-infected human intestinal epithelial cells int407 was determined by quantitative real-time rt-pcr and secretion measured by elisa. incubation of int407 with v. cholerae o395 resulted in increased il-8 mrna expression as early as within 2 h of infection. kinetics of il-8 secretion reached a peak at about 8 h (780 pg/ml) and decreased thereafter. induction of il-8 was significantly high among various toxin-producing strains of v. cholerae bel ... | 2004 | 15158775 |
| nmr structure of a type ivb pilin from salmonella typhi and its assembly into pilus. | the structure of the n-terminal-truncated type ivb structural pilin (t-pils) from salmonella typhi was determined by nmr. although topologically similar to the recently determined x-ray structure of pilin from vibrio cholerae toxin-coregulated pilus, the only type ivb pilin with known structure, t-pils contains many distinct structural features. the protein contains an extra pair of beta-strands in the n-terminal alphabeta loop that align with the major beta-strands to form a continuous 7-strand ... | 2004 | 15159389 |
| [a comparative analysis of genomes of virulent and avirulent strains of vibrio cholerae o139]. | a comparative analysis of the genome of v. cholerae o139 strains isolated in russia's territory from patients with cholera and from the environment showed essential differences in their structures. the genome of clinical strains possessed all tested genes associated with virulence (ctxab, zot, ace, rstc, rtxa, hap, toxr and toxt) and the at-trs site for the ctxp phage dna integration. as for the o139 v. cholerae chromosome strains isolated from water, 70% of the studied genes (ctxab, zot, ace, r ... | 2004 | 15164715 |
| multiplex pcr allows simultaneous detection of pathogens in ships' ballast water. | there is enormous potential for global transfer of microorganisms, including pathogens, in ships' ballast water. we contend that a major advancement in the study of ballast-water microorganisms in particular, and of aquatic pathogens in general, will be expedited sample analysis, such as provided by the elegant technology of dna microarrays. in order to use dna microarrays, however, one must establish the appropriate conditions to bind target sequences in samples to multiple probes on the microa ... | 2004 | 15172815 |
| [role of moderate bacteriophage 139 in change in production of cholera toxin in a classic strain of vibrio cholerae]. | new data were obtained concerning cell sensitivity of pathogenic strains of cholera vibrions, which belong to the serogroup o1 of classical biovar, to the temperate bacteriophage k139, the native host of which is vibrio cholerae o139. molecular-genetic and biochemical studies showed that phage 139 integrated into the chromosome of strains v. cholerae o1 can change their toxigenic properties. a change in the production of cholera toxin (ct) in lysogens is associated both with an increase in the a ... | 2004 | 15174276 |
| cross-regulation in vibrio parahaemolyticus: compensatory activation of polar flagellar genes by the lateral flagellar regulator lafk. | gene organization and hierarchical regulation of the polar flagellar genes of vibrio parahaemolyticus, vibrio cholerae, and pseudomonas aeruginosa appear highly similar, with one puzzling difference. two sigma(54)-dependent regulators are required to direct different classes of intermediate flagellar gene expression in v. cholerae and p. aeruginosa, whereas the v. parahaemolyticus homolog of one of these regulators, flak, appears dispensable. here we demonstrate that there is compensatory activa ... | 2004 | 15175315 |
| incomplete correlation of serum vibriocidal antibody titer with protection from vibrio cholerae infection in urban bangladesh. | the serum vibriocidal antibody is the only recognized predictor of protection from cholera, but no seroepidemiological data have been gathered since the emergence of vibrio cholerae o139. we assessed the association between the vibriocidal antibody titer and protection from cholera in an endemic setting. although a higher baseline vibriocidal titer correlated with protection from v. cholerae o1, infection still developed in some contacts with very high titers. no association between baseline vib ... | 2004 | 15181581 |
| occurrence and distribution of vibrio cholerae in the coastal environment of peru. | the occurrence and distribution of vibrio cholerae in sea water and plankton along the coast of peru were studied from october 1997 to june 2000, and included the 1997-98 el niño event. samples were collected at four sites in coastal waters off peru at monthly intervals. of 178 samples collected and tested, v. cholerae o1 was cultured from 10 (5.6%) samples, and v. cholerae o1 was detected by direct fluorescent antibody assay in 26 out of 159 samples tested (16.4%). based on the number of choler ... | 2004 | 15186348 |
| polylysogeny and prophage induction by secondary infection in vibrio cholerae. | strains of vibrio cholerae o1, biotypes el tor and classical, were infected with a known temperate phage (phip15) and monitored over a 15-day period for prophage induction. over the course of the experiment two morphologically and three genomically distinct virus-like particles were observed from the phage-infected el tor strain by transmission electron microscopy and field inversion gel electrophoresis, respectively, whereas only one phage, phip15, was observed from the infected classical strai ... | 2004 | 15186355 |
| a proteome reference map for vibrio cholerae el tor. | a proteome reference map has been constructed for vibrio cholerae el tor, in the pi range of 4.0 to 7.0. the map is based on two-dimensional gels (2-d) and the identification, by peptide mass fingerprint, of proteins in 94 spots, corresponding to 80 abundant proteins. two strains are compared, strain n16961 and a latin american el tor strain c3294. the consensus map contains 340 spots consistently seen with both strains grown in luria-bertani broth (lb) or minimal m9 medium. the results were obt ... | 2004 | 15188416 |
| [characterization of vibrio cholerae o1 cultures isolated from environmental objects on the territory of the russian federation in 2002]. | the biological properties of 46 v. cholerae o1 eltor cultures isolated in 2002 from water environment on the territory of russia are presented. all isolated vibrios proved to be typical in their cultural, morphological, biochemical and serological properties. the atypical character of some of them was mainly linked with their phage resistance. the appearance of vibrios, sensitive to bacteriophage ctx+ and containing gene tcp in the absence gene ctx, was noted. multilocus vntr typing made it poss ... | 2004 | 15188549 |
| [transition of vibrio cholerae into the non-culturable state under the conditions of low temperature, different mineralization and illumination of artificial culture medium]. | the importance of the combined influence of temperature, mineralization and illumination of the medium on the time of the transition of v. cholerae into the uncultivable state has been shown. the reversion of 5- to 60-day variants of uncultivable forms after the elevation of temperature to 20-22 degrees c has been obtained. | 2004 | 15188550 |
| [triacylglycerol lipase activity of hemolytic vibrio cholerae]. | the new method for the determination of the lipase activity of purified preparations of hemolysins and live v. cholerae cell has been developed. on the basis of the determination of triacylglycerollipase (lipase) activity the test for the differentiation of hemolytic and nonhemolytic v. cholerae has been proposed. | 2004 | 15188551 |
| a bayesian method for identifying missing enzymes in predicted metabolic pathway databases. | the pathologic program constructs pathway/genome databases by using a genome's annotation to predict the set of metabolic pathways present in an organism. pathologic determines the set of reactions composing those pathways from the enzymes annotated in the organism's genome. most annotation efforts fail to assign function to 40-60% of sequences. in addition, large numbers of sequences may have non-specific annotations (e.g., thiolase family protein). pathway holes occur when a genome appears to ... | 2004 | 15189570 |
| biosafety aspects of the recombinant live oral vibrio cholerae vaccine strain cvd 103-hgr. | the development of live attenuated vaccines, allowing for the safe and effective immunisation at mucosal surfaces, is a strategy of great interest for vaccinologists. the main advantage of this approach over conventional parenteral vaccines is the induction of strong mucosal immune responses, allowing targeting of the pathogen at the initial point of contact with the host. further advantages include the ease of administration, high acceptance by vaccines, and relatively low production costs. fin ... | 2004 | 15193410 |
| effect of w07-toxin on gut physiological response in mice. | a number of unknown secretogenic factor(s) from vibrio cholerae have been implicated to play a role in inducing cholera-like symptoms observed in patients. the present study has been carried out on the novel w07-toxin (pi 5.2) from v. cholerae w07, an epidemic cholera strain devoid of the ctx gene. the toxin showed maximum binding to gm(1) and interacted with a 20 kda glycoprotein present on the cell membrane of mice enterocytes in a gm(1) specific manner. the analysis of biochemical parameters ... | 2004 | 15194154 |
| the value of cholera vaccination in promoting travel health. | cholera is a diarrhoeal disease caused by intestinal infection with vibrio cholerae bacterium (health protection agency, 2004). travellers are now able to obtain a cholera vaccine in the uk. although cholera is rare in travellers from the uk, its potential severity is a cause for concern. nurses will need to consider the availability of this new vaccine when providing health promotion to travellers. | 2004 | 15195540 |
| cpg dna, liposome and refined antigen oral cholera vaccine. | an oral cholera vaccine made up of three vibrio cholerae antigens, i.e. lipopolysaccharide (lps), recombinant toxin co-regulated pili (rtcpa) and heat-treated cholera toxin (h-ct) has been developed in six different formulations. eight-week-old wistar rats were divided into nine groups and immunized as follows: the first group received the oral vaccine 1 consisting of the three antigens (lps, rtcpa and h-ct) associated with a liposome (l) and bacterial cpg-dna (odn#1826). the rats of groups 2 an ... | 2003 | 15198341 |
| identification of a domain within the multifunctional vibrio cholerae rtx toxin that covalently cross-links actin. | the gram-negative pathogen vibrio cholerae causes diarrheal disease through the export of enterotoxins. the v. cholerae rtx toxin was previously identified and characterized by its ability to round human laryngeal epithelial (hep-2) cells. further investigation determined that cell rounding is caused by the depolymerization of actin stress fibers, through the unique mechanism of covalent actin cross-linking. in this study, we identify a domain within the full-length rtx toxin that is capable of ... | 2004 | 15199181 |
| cholera toxin: a paradigm for multi-functional engagement of cellular mechanisms (review). | cholera toxin (ctx) from vibrio cholerae and its closely related homologue, heat-labile enterotoxin (etx) from escherichia coli have become superb tools for illuminating pathways of cellular trafficking and immune cell function. these bacterial protein toxins should be viewed as conglomerates of highly evolved, multi-functional elements equipped to engage the trafficking and signalling machineries of cells. ctx and etx are members of a larger family of a-b toxins of bacterial (and plant) origin ... | 2004 | 15204437 |
| hutz is required for efficient heme utilization in vibrio cholerae. | vibrio cholerae, the causative agent of cholera, requires iron for growth. one mechanism by which it acquires iron is the uptake of heme, and several heme utilization genes have been identified in v. cholerae. these include three distinct outer membrane receptors, two tonb systems, and an apparent abc transporter to transfer heme across the inner membrane. however, little is known about the fate of the heme after it enters the cell. in this report we show that a novel heme utilization protein, h ... | 2004 | 15205415 |
| saturation transfer difference (std) 1h-nmr experiments and in silico docking experiments to probe the binding of n-acetylneuraminic acid and derivatives to vibrio cholerae sialidase. | saturation transfer difference (std) (1)h nmr experiments were used to probe the epitope binding characteristics of the sialidase [ec 3.2.1.18] from the bacterium vibrio cholerae, the causative agent of cholera. binding preferences were investigated for n-acetylneuraminic acid (neu5ac, 1), the product of the sialidase catalytic reaction, for the known sialidase inhibitor 5-acetamido-2,6-anhydro-3,5-dideoxy-d-glycero-d-galacto-non-2-enoic acid (neu5ac2en, 2), and for the uronic acid-based neu5ac2 ... | 2004 | 15211517 |
| newly isolated vibrio cholerae non-o1, non-o139 phages. | | 2004 | 15212001 |
| effect of anaerobiosis on expression of virulence factors in vibrio cholerae. | in vibrio cholerae, the transmembrane dna binding proteins, toxr and tcpp, activate expression of the regulatory gene toxt in response to specific environmental signals. the resulting enhanced level of toxt leads to a coordinated increase in the production of a subset of virulence factors, including cholera toxin (ct) and toxin-coregulated pilus (tcp). the effect of anaerobiosis on expression of the v. cholerae virulence regulatory cascade was examined. the expression of the major regulatory gen ... | 2004 | 15213140 |
| synthetic fragments of vibrio cholerae o1 inaba o-specific polysaccharide bound to a protein carrier are immunogenic in mice but do not induce protective antibodies. | development of vibrio cholerae lipopolysaccharide (lps) as a cholera vaccine immunogen is justified by the correlation of vibriocidal anti-lps response with immunity. two v. cholerae o1 lps serotypes, inaba and ogawa, are associated with endemic and pandemic cholera. both serotypes induce protective antibody following infection or vaccination. structurally, the lpss that define the serotypes are identical except for the terminal perosamine moiety, which has a methoxyl group at position 2 in ogaw ... | 2004 | 15213154 |
| transcriptional responses of intestinal epithelial cells to infection with vibrio cholerae. | vibrio cholerae is a noninvasive enteric bacterium that causes the severe diarrheal disease cholera. candidate cholera vaccines have been engineered by deleting genes encoding known virulence factors in v. cholerae; however, many of these attenuated strains were still reactogenic in human volunteers. in this study, dna arrays were utilized to monitor the transcriptional responses of human intestinal epithelial cells (t84) to eight strains of v. cholerae, including attenuated, toxigenic, and envi ... | 2004 | 15213169 |
| nontypeable haemophilus influenzae strain 2019 produces a biofilm containing n-acetylneuraminic acid that may mimic sialylated o-linked glycans. | previous studies suggested that nontypeable haemophilus influenzae (nthi) can form biofilms during human and chinchilla middle ear infections. microscopic analysis of a 5-day biofilm of nthi strain 2019 grown in a continuous-flow chamber revealed that the biofilm had a diffuse matrix interlaced with multiple water channels. our studies showed that biofilm production was significantly decreased when a chemically defined medium lacking n-acetylneuraminic acid (sialic acid) was used. based on these ... | 2004 | 15213170 |
| antibiotic resistance conferred by a class i integron and sxt constin in vibrio cholerae o1 strains isolated in laos. | changes in the drug susceptibility pattern were observed in vibrio cholerae o1 isolated in the lao people's democratic republic during 1993 to 2000. in this study, 50 v. cholerae o1 strains were selected during this period for studying the presence of class i integron and sxt constin. twenty-four streptomycin-resistant strains out of 26 isolated before 1997 contained a class i integron harboring the aada1 gene cassette. twenty-four strains isolated after 1997 contained an sxt constin (a large co ... | 2004 | 15215082 |
| vibrio cholerae apha uses a novel mechanism for virulence gene activation that involves interaction with the lysr-type regulator aphb at the tcpph promoter. | apha is required for expression of the vibrio cholerae virulence cascade and for its regulation by quorum sensing. in order to activate transcription, apha functions together with a second protein, the lysr-type regulator aphb, at the tcpph promoter. as apha is a member of a new and largely uncharacterized regulator family, random mutagenesis was used to gain insights into how this protein activates transcription. as shown here, 17 amino acid substitutions were identified in apha that reduced ex ... | 2004 | 15225309 |
| hfq is essential for vibrio cholerae virulence and downregulates sigma expression. | hfq is an rna-binding protein that interacts with both small untranslated rnas (srnas) and mrnas to modulate gene expression post-transcriptionally. in escherichia coli and salmonella typhimurium, hfq is required for efficient expression of the stationary phase sigma factor sigma(s), and consequently is critical for salmonella virulence. we have found that hfq is also essential for the virulence of vibrio cholerae, as strains lacking hfq fail to colonize the suckling mouse intestine. deletion of ... | 2004 | 15225327 |
| sialic acid recognition by vibrio cholerae neuraminidase. | vibrio cholerae neuraminidase (vcna) plays a significant role in the pathogenesis of cholera by removing sialic acid from higher order gangliosides to unmask gm1, the receptor for cholera toxin. we previously showed that the structure of vcna is composed of a central beta-propeller catalytic domain flanked by two lectin-like domains; however the nature of the carbohydrates recognized by these lectin domains has remained unknown. we present here structures of the enzyme in complex with two substr ... | 2004 | 15226294 |
| molecular analysis of rugosity in a vibrio cholerae o1 el tor phase variant. | reversible phase variation between the rugose and smooth colony variants is predicted to be important for the survival of vibrio cholerae in natural aquatic habitats. microarray expression profiling studies of the rugose and smooth variants of the same strain led to the identification of 124 differentially regulated genes. further expression profiling experiments showed how these genes are regulated by the vpsr and hapr transcription factors, which, respectively, positively and negatively regula ... | 2004 | 15228530 |
| the vibrio cholerae flgm homologue is an anti-sigma28 factor that is secreted through the sheathed polar flagellum. | vibrio cholerae has a single polar sheathed flagellum that propels the cells of this bacterium. flagellar synthesis, motility, and chemotaxis have all been linked to virulence in this human pathogen. v. cholerae expresses flagellar genes in a hierarchy consisting of sigma54- and sigma28-dependent transcription. in other bacteria, sigma28 transcriptional activity is controlled by an anti-sigma28 factor, flgm. we demonstrate that the v. cholerae flgm homologue (i) physically interacts with sigma28 ... | 2004 | 15231794 |
| biological activity of five antibacterial flavonoids from combretum erythrophyllum (combretaceae). | preliminary studies with combretum erythrophyllum showed antimicrobial activity against gram-positive and gram-negative bacteria. seven antibacterial flavonoids were subsequently isolated by bioassay-guided fractionation, i.e. apigenin; genkwanin; 5-hydroxy-7,4'-dimethoxyflavone, rhamnocitrin; kaempferol; quercetin-5,3'-dimethylether; rhamnazin. all compounds had good activity against vibrio cholerae and enterococcus faecalis, with mic values in the range of 25-50 microg/ml. rhamnocitrin and que ... | 2004 | 15234754 |
| cholera toxin prevents th1-mediated autoimmune disease by inducing immune deviation. | cholera toxin (ct), a major enterotoxin produced by vibrio cholerae, is known for its properties as a mucosal adjuvant that promotes th2 or mixed th1 + th2 responses. in this study, we explore the ability of ct to act as a systemic adjuvant to counteract the th1 response leading to experimental autoimmune uveitis. we report that susceptible b10.riii mice immunized with a uveitogenic regimen of the retinal ag interphotoreceptor retinoid-binding protein could be protected from disease by a single ... | 2004 | 15240661 |
| synchronous replication initiation of the two vibrio cholerae chromosomes. | | 2004 | 15242627 |
| small rnas shed some light. | small regulatory rnas can act by pairing with their target messages, targeting themselves and the mrna for degradation; lenz et al. (this issue of cell) now report that multiple small rnas are essential regulators of the quorum-sensing systems of vibrio species, including the regulation of virulence in v. cholerae. | 2004 | 15242637 |
| the small rna chaperone hfq and multiple small rnas control quorum sensing in vibrio harveyi and vibrio cholerae. | quorum-sensing bacteria communicate with extracellular signal molecules called autoinducers. this process allows community-wide synchronization of gene expression. a screen for additional components of the vibrio harveyi and vibrio cholerae quorum-sensing circuits revealed the protein hfq. hfq mediates interactions between small, regulatory rnas (srnas) and specific messenger rna (mrna) targets. these interactions typically alter the stability of the target transcripts. we show that hfq mediates ... | 2004 | 15242645 |
| newcastle disease virus neuraminidase primes neutrophils for stimulation by galectin-3 and formyl-met-leu-phe. | human neutrophils are activated by the beta-galactoside-binding lectin galectin-3, provided that the cells are primed by in vivo extravasation or by in vitro preactivation with, for example, lps. removal of terminal sialic acid can change neutrophil functionality and responsiveness due to exposure of underlying glycoconjugate receptors or change in surface charge. here, we investigated whether such alteration of the cell surface carbohydrate composition can alter the responsiveness of the cells ... | 2004 | 15242763 |
| a new family of conditional replicating plasmids and their cognate escherichia coli host strains. | we constructed a family of conditionally replicating plasmids, the ptx1 family, which are based on the incpalpha oriv origin of replication that is dependent on the trfa-encoded protein. we constructed several escherichia coli derivatives expressing trfa from different chromosomal loci, which can be transduced by phage p1 to any e. coli strain. the ptx1 plasmids also carry the oritrp4 origin of transfer, and can be conjugated to e. coli, vibrio cholerae and likely to a broad range of bacteria fr ... | 2004 | 15249062 |
| a cholera epidemic in a rural area of northeast india. | sporadic cases of acute diarrhoea with high morbidity occur commonly in rural areas of northeast india, throughout the year. at times they take epidemic form and one such outbreak occurred with attack and case fatality rates of 11.6% and 0.8%, respectively, in october 2002, in a remote locality of assam. vibrio cholerae o1 el tor ogawa was isolated in 63% of hospitalized acute diarrhoea patients. ineffective antibacterial treatment, poor hygiene practices and bad peridomestic sanitation were the ... | 2004 | 15251406 |
| cyclic diguanylate (c-di-gmp) regulates vibrio cholerae biofilm formation. | while studying virulence gene regulation in vibrio cholerae during infection of the host small intestine, we identified viea as a two-component response regulator that contributes to activating expression of cholera toxin. here we report that viea represses transcription of vibrio exopolysaccharide synthesis (vps) genes involved in biofilm formation by a mechanism independent of its phosphorelay and dna-binding activities. viea controls the intracellular concentration of the cyclic nucleotide se ... | 2004 | 15255898 |
| vibrio cholerae biofilms: stuck between a rock and a hard place. | | 2004 | 15262913 |
| the sodium-driven flagellar motor controls exopolysaccharide expression in vibrio cholerae. | vibrio cholerae causes the life-threatening diarrheal disease cholera. this organism persists in aquatic environments in areas of endemicity, and it is believed that the ability of the bacteria to form biofilms in the environment contributes to their persistence. expression of an exopolysaccharide (eps), encoded by two vps gene clusters, is essential for biofilm formation and causes a rugose colonial phenotype. we previously reported that the lack of a flagellum induces v. cholerae eps expressio ... | 2004 | 15262923 |
| the ompu paralogue vca1008 is required for virulence of vibrio cholerae. | we made single and combined mutations in ompu, ompt, and the two putative porin genes vca1008 and vc0972. the fitness of the strains was tested in vitro and in the infant mouse model of intestinal infection. we also studied the transcriptional induction of vca1008 in vitro and during mouse infection. we show that vca1008 is induced during infection and is necessary and sufficient (in the absence of ompu, ompt, and vc0972) for infection. | 2004 | 15262955 |
| the major subunit of the toxin-coregulated pilus tcpa induces mucosal and systemic immunoglobulin a immune responses in patients with cholera caused by vibrio cholerae o1 and o139. | diarrhea caused by vibrio cholerae is known to give long-lasting protection against subsequent life-threatening illness. the serum vibriocidal antibody response has been well studied and has been shown to correlate with protection. however, this systemic antibody response may be a surrogate marker for mucosal immune responses to key colonization factors of this organism, such as the toxin-coregulated pilus (tcp) and other factors. information regarding immune responses to tcp, particularly mucos ... | 2004 | 15271902 |
| antimicrobial use in children under five years with diarrhea in a central region province, thailand. | this cross-sectional study aimed to estimate the prevalence of appropriate antimicrobial prescribing for treating childhood diarrhea within the public hospital system in a central region province, thailand. reported are findings of a prospective clinical audit of 424 cases treated by 38 physicians. appropriate use of antimicrobials was defined as prescribing antimicrobials for managing an invasive bacterial-type, bloody diarrhea or not prescribing antimicrobials for managing a watery-type or non ... | 2004 | 15272767 |
| application of oligonucleotide array technology for the rapid detection of pathogenic bacteria of foodborne infections. | a rapid and accurate method for detection for common pathogenic bacteria in foodborne infections was established by using oligonucleotide array technology. nylon membrane was used as the array support. a mutation region of the 23s rrna gene was selected as the discrimination target from 14 species (genera) of bacteria causing foodborne infections and two unrelated bacterial species. a pair of universal primers was designed for pcr amplification of the 23s rrna gene. twenty-one species (genera)-s ... | 2004 | 15279944 |
| nhaa of escherichia coli, as a model of a ph-regulated na+/h+antiporter. | na(+)/h(+) antiporters are ubiquitous membrane proteins that are involved in homeostasis of h(+) and na(+) throughout the biological kingdom. corroborating their role in ph homeostasis, many of the na(+)/h(+) antiporter proteins are regulated directly by ph. the ph regulation of nhaa, the escherichia coli na(+)/h(+) antiporter (ecnhaa), as of other, both eukaryotic and prokaryotic na(+)/h(+) antiporters, involves a ph sensor and conformational changes in different parts of the protein that trans ... | 2004 | 15282168 |
| spectroscopic characterization of the soluble guanylate cyclase-like heme domains from vibrio cholerae and thermoanaerobacter tengcongensis. | soluble guanylate cyclase (sgc) is a nitric oxide- (no-) sensing hemoprotein that has been found in eukaryotes from drosophila to humans. prokaryotic proteins with significant homology to the heme domain of sgc have recently been identified through genomic analysis. characterization of two of these proteins is reported here. the first is a 181 amino acid protein cloned from vibrio cholerae (vca0720) that is encoded in a histidine kinase-containing operon. the ferrous unligated form of vca0720 is ... | 2004 | 15287748 |
| role of nitric oxide in nag-st induced store-operated calcium entry in rat intestinal epithelial cells. | this study was undertaken to find out the mechanism of non-agglutinable vibrio cholerae heat-stable enterotoxin (nag-st)-induced calcium influx across the plasma membrane. adriamycin, an inhibitor of ip3-specific 3-kinase, could not inhibit nag-st-induced calcium influx in rat intestinal epithelial cells, which suggested that inositol 1,3,4,5-tetrakisphosphate (ip4) had no role in nag-st-induced calcium influx. nag-st increased intracellular nitric oxide level of rat enterocytes as measured by a ... | 2004 | 15297024 |
| characteristics of vibrio cholerae proteinases: potential, candidate vaccine antigens. | vibrio cholerae extracellular proteinases (proteases) have been studied as potential candidate antigens for acellular cholera vaccines. proteinases from v. cholerae nctc 10732 were prepared from batch culture either by ammonium sulphate precipitation and g100 sephadex gel filtration or by isoelectric focusing (ief). proteinase activity was at a maximum level after 24 h, coincident with the late exponential phase and early stationary phase. three major ief peaks of activity were resolved with spe ... | 2004 | 15297052 |
| functional analysis of the alpha-defensin disulfide array in mouse cryptdin-4. | the alpha-defensin antimicrobial peptide family is defined by a unique tridisulfide array. to test whether this invariant structural feature determines alpha-defensin bactericidal activity, mouse cryptdin-4 (crp4) tertiary structure was disrupted by pairs of site-directed ala for cys substitutions. in a series of crp4 disulfide variants whose cysteine connectivities were confirmed using nmr spectroscopy and mass spectrometry, mutagenesis did not induce loss of function. to the contrary, the in v ... | 2004 | 15297466 |
| antimicrobial resistance in selected bacterial enteropathogens in north india. | the resistance of enteropathogenic bacteria to commonly prescribed antibiotics is increasing both in developing as well as in developed countries. resistance has emerged even to newer, more potent antimicrobial agents. the present study was therefore undertaken to report the current antibiotic resistance in common bacterial enteropathogens isolated in a tertiary care hospital in north india. | 2004 | 15299231 |
| a three-dimensional model for the substrate binding domain of the multidrug atp binding cassette transporter lmra. | multidrug resistance presents a major obstacle to the treatment of infectious diseases and cancer. lmra, a bacterial atp-dependent multidrug transporter, mediates efflux of hydrophobic cationic substrates, including antibiotics. the substrate-binding domain of lmra was identified by using photo-affinity ligands, proteolytic degradation of lmra, and identification of ligand-modified peptide fragments with matrix-assisted laser desorption ionization/time of flight mass spectrometry. in the nonener ... | 2004 | 15304548 |
| drug susceptibility and its genetic basis in epidemic vibrio cholerae o1 in vietnam. | the drug susceptibility and genes responsible for the drug resistance of vibrio cholerae o1 isolated in vietnam in 1995, 2000 and 2002 were studied. the strains isolated in 1995 were resistant to streptomycin and harboured the class i integron which contained the aada1 gene responsible for streptomycin resistance. the strains isolated in 2000 were devoid of a class i integron but were multiple-drug resistant and harboured sxt constin, with several drug-resistant genes. the genes responsible for ... | 2004 | 15310160 |
| [excess mortality by diarrhea simultaneous to a cholera epidemic in northeastern brazil]. | to evaluate excess mortality due to infectious diarrhea without etiological diagnosis, occurring simultaneously to vibrio cholerae circulation. | 2004 | 15311291 |
| non-o1 vibrio cholerae septicemia: case report, discussion of literature, and relevance to bioterrorism. | non-o1 vibrio cholerae (novc) is a rare cause of septicemia in the united states. we report a case of novc septicemia and discuss the literature pertaining to this organism. novc takes on new significance given that it can be confused with toxigenic v. cholerae, a centers for disease control and prevention category b bioterrorism agent. | 2004 | 15313536 |
| cholera, 2003. | | 2004 | 15315149 |
| growth inhibition of enteric pathogens by zinc sulfate: an in vitro study. | to determine the inhibition effect of zinc sulfate on isolates of enteric bacteria. | 2004 | 15316263 |
| regulation of ribosomal protein synthesis in vibrio cholerae. | we have investigated the regulation of the s10 and spc ribosomal protein (r-protein) operons in vibrio cholerae. both operons are under autogenous control; they are mediated by r-proteins l4 and s8, respectively. our results suggest that escherichia coli-like strategies for regulating r-protein synthesis extend beyond the enteric members of the gamma subdivision of proteobacteria. | 2004 | 15317799 |
| identification of operators and promoters that control sxt conjugative transfer. | transfer of sxt, a vibrio cholerae-derived integrating conjugative element that encodes multiple antibiotic resistance genes, is repressed by setr, a lambda434 ci-related repressor. here we identify divergent promoters between s086 and setr that drive expression of the regulators of sxt transfer. one transcript encodes the activators of transfer, setc and setd. the second transcript codes for setr and, like the ci transcript of lambda, is leaderless. setr binds to four operators located between ... | 2004 | 15317801 |
| inactivation of enteric microbes in water by electro-chemical oxidant from brine (nacl) and free chlorine. | oxidant solutions of mostly free chlorine can be electrochemically produced on-site from brine (nacl) solution and used to disinfect water at the household or community level. in this study electrochemical oxidant (eco) from brine and free chlorine were evaluated under laboratory conditions for inactivation of test microbes. purified suspensions of escherichia coli, the rugose strain of vibrio cholerae, clostridium perfringens spores, ms2 coliphage and cryptosporidium parvum oocysts were treated ... | 2004 | 15318500 |
| evaluation of a rapid polymerase chain reaction based identification technique for vibrio cholerae isolates. | rapid and accurate identification of waterborne pathogens, such as vibrio cholerae, in drinking-water sources is important to enable effective resource management and public health protection. phenotypic systems currently being used for the identification of vibrio cholerae isolates are time-consuming and the need exists for the development of suitable molecular techniques that can offer both fast and reliable identification. during this study, isolates identified as vibrio cholerae by means of ... | 2004 | 15318514 |
| vibrio cholerae in the environment. | the emergence of cholera has been a significant public health problem around the world and battle to completely control this deadly disease continues. prevalence of vibrio cholerae (v. cholerae) microorganisms in the environment was considered as the most important factor in this regard. soil, fresh water, sea water, aquatic plants, animals and some birds have been made target for search if they were providing reserve shelter to the causative agent during inter epidemic periods. multiple environ ... | 2004 | 15321050 |
| competitive growth advantage of nontoxigenic mutants in the stationary phase in archival cultures of pathogenic vibrio cholerae strains. | spontaneous nontoxigenic mutants of highly pathogenic vibrio cholerae o1 strains accumulate in large numbers during long-term storage of the cultures in agar stabs. in these mutants, production of the transcriptional regulator toxr was reduced due to the presence of a mutation in the ribosome-binding site immediately upstream of the toxr open reading frame. consequently, the toxr-dependent virulence regulon was turned off, with concomitant reduction in the expression of cholera toxin and toxin-c ... | 2004 | 15322049 |
| a novel recombinant multisubunit vaccine against chlamydia. | the administration of an efficacious vaccine is the most effective long-term measure to control the oculogenital infections caused by chlamydia trachomatis in humans. chlamydia genome sequencing has identified a number of potential vaccine candidates, and the current challenge is to develop an effective delivery vehicle for induction of a high level of mucosal t and complementary b cell responses. vibrio cholerae ghosts (vcg) are nontoxic, effective delivery vehicles with potent adjuvant propert ... | 2004 | 15322201 |
| elasticity of flagellar hooks. | | 2004 | 15332658 |
| [association between vibrio cholerae and zooplankton of estuaries of são marcos bay/são luis - ma, brazil]. | this study was carried from october 1997 to october 1998 with the purpose of investigating the link between the species vibrio cholerae and zooplankton in the estuaries of rivers anil and bacanga in são luis, maranhão. research of viable but non culturable forms of vibrio cholerae o1, and analyze the correlation between ph values, salinity and water temperature with the presence of bacteria in zooplankton samples. the traditional method of cultivation and fluorescent antibody technique were appl ... | 2004 | 15334265 |
| [molecular study of vibrio cholerae non-o1 isolated from zooplankton of são marcos bay/são luis - ma, brasil]. | the study was developed to analyze the plasmidial dna, research virulence genes and identify genetic diversity of 31 strains of vibrio cholerae non-o1 isolated from zooplankton of the bacanga and anil rivers in são luis-ma. the study of plasmidial dna showed 2 or 3 plasmids from 10 strains between 5.5 and 40 kilobasis. there was only single ribotype pattern. pcr methods did not show the genes ctxa, ace and zot, while radp-pcr identified genetic diversity in the strains, showing the potential for ... | 2004 | 15334266 |
| [discordancies between classical and api 20e microtest biochemical identification of vibrio and aeromonas strains]. | the present study reveals some discordancies of diagnosis considering vibrionaceae strains when tested by comparison with api 20e (biomerieux) system and classical biochemical reactions, aspects already mentioned in the literature by other authors. if any misidentification has not an important impact (e.g. identification of aeromonas schubertii as a. sobria), others as misidentification of aeromonas as vibrio strains or the failure to recognize vibrio strains raise major epidemiological problems ... | 2003 | 15341329 |
| [comparative study of classical and commercial microtest api galleries in the diagnosis of cholera infection]. | cholera still remains in the top of causes generating global mortality and morbidity, as revealed by the latest who reports. in 2000, on cdc/atlanta website, the cholera agent was mentioned as potential biological weapon for bioterrorism actions in 9460 publications. considering these aspects, a correct and rapid diagnosis is necessary in order to take appropriate epidemiological measures and to prevent the secondary transmission. our study evaluated the efficiency of microtest systems api20e, a ... | 2003 | 15341330 |
| cholera epidemic associated with raw vegetables--lusaka, zambia, 2003-2004. | zambia experienced widespread cholera epidemics in 1991 (13,154 cases), 1992 (11,659), and 1999 (11,327). in response to the large outbreak in 1999, the zambian ministry of health (zmoh) urged use of in-home chlorination with the locally produced solution, clorin, and the practice increased substantially clorin had been introduced in zambia in 1998 as part of the safe water system (sws), a point-of-use water disinfection and safe-water storage strategy launched by the society for family health, ... | 2004 | 15343144 |